Legs of lead

Felt good enough to go to work today. But had weird sensations while walking. My legs felt like I had run a marathon and I had to concentrate on lifting my legs. Curious about this, at what point do those of us with MS stop wondering if this is the "time" I lose the ability to walk. If you think I was pissed off about having to use a cane, its really gonna be ugly if I have to get a "Rascal" :o)